Bobbin-controlling adjunct for sewing-machine-bobbin cases



Jan. 12 1926.

R. N. CORTHELL BOBBIN CONTROLLING ADJUNCT FOR SEWING MACHINE BOBBINCASES Filed March 17, 1925 Patented Jim. 12, 1926.

PATENT OFFICE.-

, 301mm: N. CORTHELL, or AUBURN, MAINE.

BOBBIN-CQNTROLLING ADJUNCT FOR SEWING-MACHINE-BOBBTN CASES.

Application filed Harc1117, 1925. Serial No. 16,198.

To all whom, it may concern:

Be it known that I, ROBERT-N- Con'rrrnnn, a citizen of the UnitedStates, residing at Auburn, in the county of And goscoggin and State ofMaine, have invented new and useful Improvements in Bobbin-ControllingAdjuncts for Sewing-Machine-Bobbin Cases, of which the following is aspecification.

This invention relates to the bobbin case of a sewing-machine shuttle,the bobbinreceiving cavity of the bobbin case being closed at one end bya head. The cavity is adapted to receive a ready-wound bobbin, composedof a cop tube and a thread winding thereon, the bobbin being rotatableon a center post projecting from the head.

[The rotation of the bobbin is controlled by resilient means, interposedbetween the head and the adjacent end face of the bobbin, and a thrustbearing against which the other end face of the bobbinis pressed by saidresilient means.

The continuity of the head in a bobbin (7858.0f the above-mentioned typeis inter-' rupted by orifices permitting. a circulation of air in thecavity,-and the escape of lint therefrom. Said orifices are located inthe marginal portion of the head, and are spaced from'the center'post bya continuous or uninterrupted central portion of the head.

The object of the invention is to provide for use with a bobbin case ofthe above-mentioned type, a bobbin-controlling adjunct of extremesimplicity and made in a single piece adapted to bear on practically theentire mner end face of the bobbin, and to bear movably on theuninterrupted central portion of the head, without interference with themargins of the orifices in the head.

The construction whereby this object is attained, and the advantagesthereof, are hereinafter set forth.

Of theaccompanying drawings forming a part of this specification Thesame reference characters indicate the same parts in all of the figures.

Figures 1 and 2 show a bobbin case of the type above mentioned, to whichmy improved adjunct is applicable. The bobbin case includes a head 12,forming one end of a bobbin cavity, adapted to receive a bobbin whichmay be of the ready-wound variety, and composed of a tube or core 13,and a thread winding 14. The bobbin is rotatable on a center post 15,fixed to the head. A swinging latch 16, yieldingly retained by wellknown means in the position shown by Figure 2, constitutes a thrustbearing against which the outer end face of the bob bin is pressed, ashereinafter described, the latch being movable to a position inalinement with the post, to permit the insertion and removal of thebobbin, in the usual manner.

In this type of bobbin case the head 12 is provided with orifices 17,located near the margin of the head, to permit the escape of lint fromthe bobbin cavity, and permit a cooling circulation of air around thebobbin. Said orifices interrupt the continuity of the marginal portionof the head, and their walls intersect the inner face of the head, andthereby form shoulders at the outer portion of the head.

The central portion of the head surrounding the post is invariablycontinuous or uninterrupted. I utilize this continuous portion tosupport my improved bobbin-controlling adjunct, which is so formed thatit bears only on the continuous central portion of the head, and is freefrom liability to interference with said shoulders.

Said adjunct is composed of a flat disk 18, of thin resilient sheetmetal, formed to enter the bobbin cavity and bear on substantially theentire inner end face of the bobbin, said disk having a central orifice18 receiving the post 15, and inclined spring tongues 19, integral withthe disk,1extend ing'inward from opposite marginal portions of the disktoward the post, and laterally from the disk toward the head, theperiphery of the disk being continuous and maintaining the flat form ofthe disk sides.

Said tongues have free end ortions 0&- set from the disk, as shown byigure 2, and arranged to bear on the continuous ce tral.

portion of the head at points between the center post and the openings17. The tongues are therefore movable on the head,

without interference with the shoulders formed by the walls of saidopenings.

Owing to the fact that the disk 18 contacts with practically allportions of the inner end face of the bobbin, its frictional engagementwith the bobbin is suflicient to cause the disk to turn with the bobbin.Owing to the fact that the tongues 19 are joined to the marginal portionof the disk, and extend inward therefrom to points in close proximity tothe center post, the tongues are adapted to revent undesirably freerotation of the bob in by their sliding contact with the continuous oruninterrupted central ortion of the head, there being no possibility ofinterference between the tongues and the walls of the openings. The diskand its tongues, therefore, constitute a one-piece bobbin-controllingadjunct, adapted to be applied as a unit to a bobbin case havingopenings in the outer portion of its head, and free from liability ofinterference between-the ton use and the margins of the openings, and te injurious results of such interference, such as the breakage ofthetongues and the catching of the needlethread by a tongue protrudingthrough an orifice. Y

T he described arrangement-of the tongues obviates the necessity ofemploying means independent of the disk, and tongues for preventinginterference between the tongues and the margins; of the head orifices.The tongues are tensioned -by the insertion of the bobbin in the cavity,so that they press the disk against the bobbin and the bobbin against;the thrust bearing.

.lclaim:

A bobbin-controlling adjunct for a sew ing-machine bobbin case, havingopenings in its head atone end, and a thrust bearing at the other end,said adjunct comprising a flat disk formed to enter the bobbin-receivingcavity of the bobbin case and bear on substantially the entire inner endface of a bobbin in said cavity, the disk having a central orificeadapted to receive a center post of the bobbin case, a continuousperiphery concentric with the orifice and maintainin the flat form ofthe disk, and incline tending inward from points at opposite marginalportions of the disk and within the periphery of -the latter, saidtongues having free end portion ofi'set from the disk and from thecentral orifice, and arranged to bear on the central portion of the headat points between the center post of the bobbin case and the openings inthe head, the tongues being adapted to move on the head withoutinterference with the margins of said openings, and to press the diskagainst the bobbin, and the bobbin against said-end thrust bearing atthe outer end of the cavity, the tongues being wholly within theperiphery of the disk, so that said periphery is uninterrupted and theinner side of the disk has a flat, substantially signature.

ROBERT N. CORTHELL.

